True Ports, like this Graham’s 20 Tawny Port, hail from the Douro valley in Northern Portugal, and have done so for over three hundred years. The region’s predominant soil is schist, composed of various medium-grained to coarse-grained metamorphic rocks with laminated, often flaky parallel layers of micaceous minerals. The low annual rainfall makes this probably one of the driest regions of the world where grapes are grown without irrigation. This terroir results in very low-yielding vineyards, with vines bearing only a very few small bunches of full-flavored grapes whose thick skins protect them from dehydration.
